At this time of year, fireplaces tend to be the focal point of many family gatherings, romantic interludes and toe-warming respites. Still, the typical masonry model is not the most efficient or environmentally sensitive heating source, according to federal agencies that regulate energy and protect the environment.

To help you choose the most eco-friendly fireplace options, we consulted fireplace regulators and industry representatives. The products they discussed are either built into the existing hearth or free-standing. They tend to produce less pollution than standard fireplaces.

For starters, consumers should decide whether they are interested in a fireplace primarily for heating throughout the winter or for decorative purposes with a few fires a year, says John Crouch, director of public affairs for the Hearth, Patio & Barbecue Association (HPBA), an international trade organization.

“The traditional open wood-burning fireplace is not a heating device as it was back in the 19th century,” he says. Hundreds of years ago, 50 degrees was also considered warm enough to heat a room, Crouch adds.

In areas with milder winters, a decorative fireplace or “hearth appliance” captures the look and feel of a fire with gas logs, fire logs or ethanol. While relatively inexpensive, these options don’t tend to provide much warmth, he says.

For more serious heat, Crouch suggests consumers consider fireplace inserts or stoves that use wood, gas or pellets made from compressed sawdust. Such systems generally have a higher price tag and require more maintenance.

Here are a few options when seeking an eco-friendly fireplace or appliance for aesthetics rather than efficiency:

Bio-ethanol fireplaces: The biofuel used in this appliance, also called ethyl alcohol, is derived from agricultural products, primarily corn, Crouch says. Ethanol fireplaces (at right) tend to have sleek contemporary designs and be used in urban settings instead of natural gas, he says. But they are not for serious heat.

“They are just decorative and their primary advantage is that they do not have to be vented,” HPBA spokeswoman Leslie Wheeler says. “You can put them anywhere.”

Gas logs (natural gas or LP, liquid propane): Gas logs can be retrofitted in an existing fireplace as an alternative to wood, according to the U.S. Environmental Protection Agency, which certifies heating appliances.

Although gas logs (at right) burn fossil fuels, either natural gas or LP, they still have low emissions, the EPA reported on its Burn Wise website.

LP gas costs more than natural gas and contains more carbon, but burns about three times hotter, according to Lowe’s gas log buying guide. LP gas comes from a tank outside the home, while natural gas is piped in as for other appliances, the home improvement store explains.

Gas logs can be vented or vent-free. Vented logs, which operate with an open chimney flue or damper, simulate a wood-burning flame. Vent-free logs won’t give you the roaring fire effect, but provide a little more heat and may have a thermostat to maintain room temperature, Lowe’s reports.

Fire logs: The most popular is the Duraflame (at right), which is made from renewable sources such as sawdust and wax, Crouch says. The company reports online that its products produce fewer carbon emissions than firewood or gas logs.

If you’re looking for a more serious heating source, HPBA recommends choosing from these eco-friendly fireplaces:

The pellets are made from compressed sawdust, wood chips, bark, agricultural waste and other organic materials, the DOE reported in its Energy Savers article on the subject.

“They are much more convenient to operate and have much higher combustion and heating efficiencies than ordinary wood stoves or fireplaces.” As a result, pellet stoves (at right) produce very little air pollution and are considered the cleanest of the solid fuel-burning residential heating appliances.

Using an automated feed system, a single load of pellets can burn 24 hours, HPBA reports.

Gas stoves: Like with gas logs, these stoves are designed to burn either natural gas or LP, EPA spokeswoman Molly Hooven says. However, gas stoves are self-contained units, while gas logs are meant to be used in an existing fireplace.

Gas stoves (at right) “emit very little pollution, require little maintenance and can be installed almost anywhere in the home,” Hooven says. “Today’s gas stoves can be vented through an existing chimney or direct vented through the wall behind the stove.”

The EPA does not support vent-free models because of indoor air quality concerns, she says.

Gas stoves are among the cleanest and cheapest fuel options, Crouch says. Although they still burn fossil fuels, they produce lower emissions than wood or other alternatives.

Some of the more innovative gas stoves incorporate stone and cut glass into the classic design with a linear line of fire, Wheeler says.

Wood-burning stoves and inserts: Most firewood grows locally, is abundant, inexpensive and “comes from harvesting dead trees,” according to the HPBA consumer report. Unlike with fossil fuels, no net carbon is released into the environment when wood is burned because the same gases are given off when the tree decomposes, the report states.

With new technology, wood stoves are capable of heating an entire house, as long as it’s well constructed with enough insulation, HPBA reports. The drawback to burning wood is you have to empty the ashes more often, Crouch says, and to split, stock, dry and season the wood to meet federal standards.

Stricter government regulations are helping to improve air quality, promoting cleaner-burning appliances, Wheeler says. Newer models allow for a more complete combustion, sending less smoke up the stack and into the atmosphere, she says.